Fiber To The Home (FTTH) is difficult to be run in a building, which is the main factor affecting the commercial scale application of the FTTH. Due to a complicated environment, laying an indoor optical cable is a great challenge for deployment of an FTTH network. The major problems are as follows.
(1) A common vertical wired product needs to be diverged and connected in a stair well. Not only a professional person and tool but also a fiber distribution box occupying a large space is needed.
(2) When the product is diverged in the stair well, the connection of fiber increases the engineering cost and at the same time increases the loss of optical fibers.
(3) Space of the stair well is small, and a construction environment is poor, thereby increasing the construction difficulty.
The commercial scale application of the FTTH is affected due to the high running cost of the FTTH. In order to find a running manner having a reduced cost and initiate the commercial scale application of FTTX, the industry keeps an eye on Fiber To The MDU (Multiple Dwelling Unit) (FTTM). Compared with the FTTH, the FTTM can increase service penetration gradually, and is more beneficial to service providers.
A conventional wiring solution of an FTTM optical cable is specifically as follows.
As shown in FIG. 1, a conventional optical cable appropriate for being vertically run in a building includes a low-smoke halogen-free flame retardant sheath 101 at an outer layer and easy-to-strip optical fiber units 104 in an inner part, where glass reinforcing ribs 102 are disposed in the low-smoke halogen-free flame retardant sheath 101, and sheath reinforcing ribs identifications 103 are disposed on a corresponding outer surface.
The method of vertically running the optical cable mainly includes the following steps (it is assumed that a user lives in the second floor): (1) installing a distribution box in a basement; (2) installing a vertical optical cable; (3) windowing the outer jacket of the vertical optical cable on the fourth or higher floor (according to the length requirement); (4) selecting an optical fiber to be pulled to the second floor, and shearing the optical fiber; (5) windowing the outer jacket of the optical cable on the second floor; (6) drawing the optical fiber sheared on the fourth floor; and (7) connecting the drawn optical fiber to the user premise.
Disadvantages of the above solution are as follows. Firstly, the length of the drawn optical fiber is limited to a certain extent, and if a distance to home of a customer is long, a further connection is required; secondly, the optical fiber needs to be windowed and sheared on an upper floor before being drawn, and interference among the optical fiber units exists during drawing; thirdly, when the number of cores of the optical cable is relatively large, the optical fiber to be sheared is difficult to be found; and fourthly, since the optical fiber unit stands in the outer jacket, the vertical height is limited, or a special measure must be adopted.